Narrative:

Having informed the tower that we were ready to takeoff, we were cleared into position and hold on runway 22. Once we had taxied into position, we were cleared for takeoff. However, after receiving clearance, both the captain and myself realized that we had forgotten to run the before takeoff checklist, and we knew there was another aircraft on final approach to runway 22. I immediately told the tower that we were not ready to takeoff, and that we would be taxiing clear of the runway to enable the approaching aircraft to land. The tower acknowledged, stating that our takeoff clearance had been cancelled, and advising the aircraft on final to make a 360 degree turn to allow us ample time to clear the runway (however, we quickly cleared the active runway, and to the best of my recollection, the tower told the other aircraft to disregard the 360 and cleared that aircraft for a straight-in landing). We completed the before takeoff checklist and taxied back to runway 22. Approaching the hold short, it became apparent that the captain was going to proceed straight onto the runway without receiving clearance from the tower. I told the captain that we weren't cleared onto the runway, but he disagreed, stating that we were still cleared into position and hold, and that only our takeoff clearance had been cancelled. Still prior to crossing the hold short line, I immediately told the tower that we were now ready to takeoff on runway 22, and noted that there were not any aircraft visible on final approach. As we were crossing the hold short line, we were cleared to takeoff by the tower. I learned several things from this flight: complacency can mean trouble. Always be alert, on guard, and never assume that everything is exactly as it should be. If a clearance or instruction is unclr, or if you feel that the other pilot is misunderstanding a clearance or instruction, request clarification with ATC prior to acting. This may mean assertion if it is the captain who is misinterpreting or does not understand a clearance and intends to take the wrong action.

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Original NASA ASRS Text

Title: COMMUTER LTT REQUESTED TKOF CLRNC BEFORE COMPLETING THE TKOF CHKLIST THEN HAD TO CLR THE RWY BECAUSE ANOTHER COMPANY ACFT WAS ON FINAL APCH.

Narrative: HAVING INFORMED THE TWR THAT WE WERE READY TO TKOF, WE WERE CLRED INTO POS AND HOLD ON RWY 22. ONCE WE HAD TAXIED INTO POS, WE WERE CLRED FOR TKOF. HOWEVER, AFTER RECEIVING CLRNC, BOTH THE CAPT AND MYSELF REALIZED THAT WE HAD FORGOTTEN TO RUN THE BEFORE TKOF CHKLIST, AND WE KNEW THERE WAS ANOTHER ACFT ON FINAL APCH TO RWY 22. I IMMEDIATELY TOLD THE TWR THAT WE WERE NOT READY TO TKOF, AND THAT WE WOULD BE TAXIING CLR OF THE RWY TO ENABLE THE APCHING ACFT TO LAND. THE TWR ACKNOWLEDGED, STATING THAT OUR TKOF CLRNC HAD BEEN CANCELLED, AND ADVISING THE ACFT ON FINAL TO MAKE A 360 DEG TURN TO ALLOW US AMPLE TIME TO CLR THE RWY (HOWEVER, WE QUICKLY CLRED THE ACTIVE RWY, AND TO THE BEST OF MY RECOLLECTION, THE TWR TOLD THE OTHER ACFT TO DISREGARD THE 360 AND CLRED THAT ACFT FOR A STRAIGHT-IN LNDG). WE COMPLETED THE BEFORE TKOF CHKLIST AND TAXIED BACK TO RWY 22. APCHING THE HOLD SHORT, IT BECAME APPARENT THAT THE CAPT WAS GOING TO PROCEED STRAIGHT ONTO THE RWY WITHOUT RECEIVING CLRNC FROM THE TWR. I TOLD THE CAPT THAT WE WEREN'T CLRED ONTO THE RWY, BUT HE DISAGREED, STATING THAT WE WERE STILL CLRED INTO POS AND HOLD, AND THAT ONLY OUR TKOF CLRNC HAD BEEN CANCELLED. STILL PRIOR TO XING THE HOLD SHORT LINE, I IMMEDIATELY TOLD THE TWR THAT WE WERE NOW READY TO TKOF ON RWY 22, AND NOTED THAT THERE WERE NOT ANY ACFT VISIBLE ON FINAL APCH. AS WE WERE XING THE HOLD SHORT LINE, WE WERE CLRED TO TKOF BY THE TWR. I LEARNED SEVERAL THINGS FROM THIS FLT: COMPLACENCY CAN MEAN TROUBLE. ALWAYS BE ALERT, ON GUARD, AND NEVER ASSUME THAT EVERYTHING IS EXACTLY AS IT SHOULD BE. IF A CLRNC OR INSTRUCTION IS UNCLR, OR IF YOU FEEL THAT THE OTHER PLT IS MISUNDERSTANDING A CLRNC OR INSTRUCTION, REQUEST CLARIFICATION WITH ATC PRIOR TO ACTING. THIS MAY MEAN ASSERTION IF IT IS THE CAPT WHO IS MISINTERPRETING OR DOES NOT UNDERSTAND A CLRNC AND INTENDS TO TAKE THE WRONG ACTION.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.